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<html>
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		<title></title>
          <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
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        <span id="span1">我草泥马</span>
        
        <input type="button" value="点我改变文本" id="btn1">
        
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            $("#span1").text("和谐, 要和谐");
            
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